Restaurant Emissions Removal By A Biofilter With Immobilized Bacteria

During the past twenty years,the use of biological air pollution control has become a popular treatment alternative for contaminated gas streams.Unlike conventional technologies,such as thermal and catalytic incineration or carbon adsorption, biofiltration allows effective pollution control at relatively low capital and operating costs, and without generation of secondary streams that may need a subsequent treatment. Biofiltration has been considered economically advantageous in the treatment of large air flow waste streams,which contain low concentrations of volatile organic and in organic compounds,typically less than 3000mg.m-3.Biofiltration units are microbial ecosystems for treatment low-concentration, biodegradable waste gases. The aim of this work was to isolate and characterize an appropriate microbial culture for inoculation of a platane wood chips biofilter that treats waste gases from restaurant using oil in its frying process. Condensate restaurant emissions used as a sole carbon source, wo bacterium strains ,named as Z1A and Z2A,which had high degrading capacity for Condensate restaurant emissions were isolated and screened out from the contaminated soil.Through morphological and biochemical method,the two strains were identified as Pseudomonas sp.Ey tests in shaking flasks it was determined that the strains can be optimum growth at 30 # ,pH7.0,inoculum amount of l%,and shaker rotary speed at 210 r/min.On the optimum conditions for growth ,the degradation rate experiments on different initial concentrations of edible oil are carried out .The result indicate that the ability of these two strains for degrading edible oil is marked. With the initial concentration of rape oil and salad oil at about 500mg/L,the degrading rates by Z1A reach 96.23% and 92.41% after 16h , respectively;the degrading rates by Z2A reach 89.7% and 95.6% after 16h , respectively.This thesis emphasized on the operational conditions and anti-shock loading capacity of the biofilter. It was demonstrated that when the contraflow was applied,the lampblack removal efficiency of the biofilter exceeded 95%, with the retention time over 8s, the lampblack concentration less than 100mg/m3, the moisture content of the filter material between 40% and 60%, and the temperature between 20 癈 and 40#. Under these conditions, the maximum biochemical removal speed of the lampblack was 64.936 g/(m3h). Besides, the device had a good anti-shock loading capacity.Based on the process of purifying gaseous low-concentration toluene,the biodegradation mechanism and the new Adsorption-Biofilm theory,a Kinetic model was set up.In further simulation study for the main factors,such as the inlet toluene concentration,the gas flux and the height of biofilm-packing,a good pertinence was showed between calculated data and test data.